According to the Log4OM data structure there are three fields that do not appear on any of the QSO tabbed screens. They are:
APP_LOG4OM_MOBILE
APP_LOG4OM_QRP
APP_LOG4OM_PORTABLE
If I am reading these correctly one is for mobile operation, one is for QRP, and the third is for portable operation. There is ample real estate on the "Contest Information" tab where you show Ten-Ten, SKCC, FISTS, and FISTS CC information.
Right now these fields are not accessible. Using the comments or notes fields does not all any type of effective sorting.
73,
Ken, AC5EZ

You are correct, those fields (Mobile, QRP and Portable) have been added to the log database structure, but they have not been added to the field layout for any of the display screens, like Recent QSO.

Possibly Lele can add those to the layout Column selection in the next maintenance release?

Those data are "old" and not used anymore by Log4OM.
Those fields was used to expedite some activities in the code that was optimized and now run in real time.

They are in the data structure, and for that reason they are FULLY exported into ADIF.

By the way those fields are not set in any part of the code anymore, except on the data structures that read/write the ADIF and the database itself, so Log4OM is keeping them alive but not adding them anymore on new QSO. Basically they're there for retro-compatibility and to mantain consistent database output in ADIF.